The scientists behind the work said it may be possible to detect these changes and predict if someone is at risk more than a decade before meeting the threshold for an Alzheimer’s diagnosis.
Janet Cohen Sherman, clinical director of the Psychology Assessment Center at Massachusetts General Hospital, said: “One of the greatest challenges right now in terms of Alzheimer’s disease is to detect changes very early on when they are still very subtle and to distinguish them from changes we know occur with normal ageing.”
Speaking at the American Association for the Advancement of Science in Boston, Sherman outlined new findings that revealed distinctive language deficits in people with mild cognitive impairment (MCI), a precursor to dementia.
“Many of the studies to date have looked at changes in memory, but we also know changes occur in language,” she said. “I’d hope in the next five years we’d have a new linguistic test.”
Sherman cites studies of the vocabulary in Iris Murdoch’s later works, which showed signs of Alzheimer’s years before her diagnosis, and the increasingly repetitive and vague phrasing in Agatha Christie’s final novels – although the crime writer was never diagnosed with dementia. Another study, based on White House press conference transcripts, found striking changes in Ronald Reagan’s speech over the course of his presidency, while George HW Bush, who was a similar age when president, showed no such decline.
“Ronald Reagan started to have a decline in the number of unique words with repetitions of statements over time,” said Sherman. “[He] started using more fillers, more empty phrases, like ‘thing’ or ‘something’ or things like ‘basically’ or ‘actually’ or ‘well’.”